Third picture is how to edit the gameinfo.txt file.
Copied from readme:
First off, open the gameinfo.txt file. Add in following line:
game+mod episodic/custom_episodic/*
To under this line:
game+mod hl2/custom/*
Then, extract the files inside this zip files straight to Half-Life 2\episodic folder. Just don't extract this file.
Hope you have fun with it. For ep2, add that same line to same spot in Half-Life 2/EP2/gameinfo.txt file.